42,648 免费图片适用于学生

生物学水下鱼海上生活动物野生动物水内华达州海洋海

Rainbow Trout-6

Pallid sturgeon-2

Largemouth bass-2

Moapa Dace

Alewife-2

Western Mosquitofish

Juvenile Dolly Varden

surgeon at work in operating room

医疗药物骨骼

Female student heart

心脏膈面学生

Rainbow Trout-1

Suwannee bass nests in a river bank-1

A scientist studying new methods for detecting foodborne bacteria directly from a patient sample. Original image sourced from US Government department: Public Health Image Library, Centers for Disease Control and Prevention. Under US law this image is copyright free, please credit the government department whenever you can”.

A field epidemiologist performing a mouth swab inside the beak of a white duck, in order to carry out an infectious disease investigation. Original image sourced from US Government department: Public Health Image Library, Centers for Disease Control and Prevention. Under US law this image is copyright free, please credit the government department whenever you can”.

Student Girl

Ash Meadows Speckled Dace-2

Juvenile yellow perch

Muskellunge

Pathway to the student union

建筑物学生

Biologists search for Fountain Darter-5

Ash Meadows Amargosa pupfish-1

A scientist preparing samples for mass spectrometry in order to determine the presence of a bacterial toxin. Original image sourced from US Government department: Public Health Image Library, Centers for Disease Control and Prevention. Under US law this image is copyright free, please credit the government department whenever you can”.

A medical illustration of Clostridioides difficile bacteria, formerly known as Clostridium difficile. Original image sourced from US Government department: Public Health Image Library, Centers for Disease Control and Prevention. Under US law this image is copyright free, please credit the government department whenever you can”.

Female student

Female student book library

Ash Meadows Amargosa pupfish-1

Hooked Smallmouth bass

Brown trout pair

Largemouth bass-1

Brook trout-1

野生动物鱼

Dolly Varden-1

Medical Doctor

Young girl with long hair is sitting in airport.

Presenting to a

非裔美国人人

Medical Doctor Man

Fetus

2 Rear view of young woman with luggage in airport

Presenting to a

非裔美国人人

Young woman with luggage in airport near flight timetable

Medical Doctor with a Yellow Card

Woman is Bathing

Mandrill

哺乳动物动物

专业领域人

卡哇伊圣情人节恐龙纸杯蛋糕

情人节恐龙

Local health centers experimenting with coronavirus. Original image sourced from US Government department: Public Health Image Library, Centers for Disease Control and Prevention. Under US law this image is copyright free, please credit the government department whenever you can”.

医疗药物科学

A photomicrograph of Candida albicans fungal spores. Original image sourced from US Government department: Public Health Image Library, Centers for Disease Control and Prevention. Under US law this image is copyright free, please credit the government department whenever you can”.

School boy

孩子们学校

school boy

孩子们学校

School boy

孩子们学校

School boy

孩子们学校

school boy

孩子们学校

School boy

孩子们学校

school boy

孩子们学校

School boy

孩子们学校

A 440X photomicrograph magnification of a hematoxylin and eosin (H&E)–stained liver tissue specimen, revealed the presence of cytoarchitectural changes indicative of fatty degeneration. Original image sourced from US Government department: Public Health Image Library, Centers for Disease Control and Prevention. Under US law this image is copyright free, please credit the government department whenever you can”.

电子学细菌

Novel Coronavirus SARS-CoV-2–Colorized scanning electron micrograph of an apoptotic cell (blue) infected with SARS-COV-2 virus particles (red), isolated from a patient sample. Original image sourced from US Government department: The National Institute of Allergy and Infectious Diseases. Under US law this image is copyright free, please credit the government department whenever you can”.

Student Girl Cries in Depression

school

孩子们学校

Chinese Pattern

中国人中国

Chinese Pattern

中国人中国

Brittle Star on Sponge

Sea turtle animal

野生动物动物

Highland shiner

Logperch-2

Ash Meadows Amargosa pupfish-1

Spotted sunfish

Ash Meadows Amargosa pupfish-1

Female Student with Smartphone

Cutthroat trout

Aquarium fish

Aquarium fish

Lake chubsucker-1

Transparent Fish Background

Brook Trout juvenile-2

野生动物鱼

Yellow bullhead catfish-1

Greenbrier Cave Crayfish

生物学样本

Pallid Sturgeon-1

Ash Meadows Amargosa pupfish-1

Teacher and formulas

Microscope - Grayscale

实验室科学

Hard Shelled Antibiotic Capsules

医疗药物药品

Captive Devils Hole pupfish-3

Ash Meadows Amargosa pupfish-6

Quilback carpsucker

Ash Meadows Amargosa pupfish-3

Ash Meadows Amargosa pupfish-1

Aquarium Fish Tank

野生动物鱼

Ash Meadows Amargosa pupfish-1

Black Fish Aquarium

Sand Colored Fish in the tank

Captive Devils Hole pupfish

Ash Meadows Amargosa pupfish-1

Close-up of bluegill with other fish

Juvenile Spotted sunfish in clear water

Black Finger Crab - Ozius truncatus

Microscope virus

实验室科学

Maldive anemonefish - Amphiprion nigripes

Devils Hole pupfish-1

Captive Devils Hole pupfish-3

Black Bullhead catfish

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